Method of building massive structures in water



Jan. 5, 1932. J. w. RICKEY METHOD OF BUILDING MASSIVE STRUCTURES IN WATER Filed March 4, 1931 '2 Sheets-Sheet WITNESSES NVENTOR J Clam- Jan. 5, 1932. J. w. RICKEY METHOD OF BUILDING MASSIVE STRUCTURES IN WATER 2 Sheets-Sheet 2 Filed March 4, 1951 Ill lllllllL ||ll llll I INV NTOR'. W 7- I I ,4 vCLzalzZW Am WE SSE S Patented Jan. 5, I932 PATENT orris JAMES W. RICKEY, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO ALUMINUM COM- PANY OF AMERICA, OF PITTSBURGH, SLYLVANIA I PENNSYLVANIA, A CORPORATION OF PENN- HETHOD OF BUILDING MASSIVE STRUCTURES IN WATER- .Application filed March 4, 1931. Serial No. 520,087.

The invention relates to the building of massive structures, such as dams, breakwaters and the like, resting upon the beds of bodies of water.

In building a structure of the type stated, the prevailing ractice is to first construct a temporary co erdam in the body of water around the intended location of the structure, pump the water from within the cofi'erdam, and erect the structure in situ. It is well known that the initial cost of a cofi'erdam is high, and that considerable expense is involved in the continual pumping required to keep it as free from water as is possible. In placing a cofl'erdam in a stream which flows at a high velocity and in large volume, the coiferdam must be proportionately strong, and usually can be constructed only in those seasons of the year when the water flow is low. In case of floods, coii'erdams are not infrequently destroyed, or filled with water, causing long and expensive delays in continuing the building of the intended structure. As an alternative to the use of cofferdams, caissons are sometimes 7 used, but they also are expensive to construct and maintain, and the uses of them are limited.

The object of this invention is to provide arpractical and economic method of build- A ing a massive structure resting upon the bed of a body of water without the use of-temporary coflerdams and the like with their attending high initial and maintenance costs.

In the practice of my invention I build a massive structure, such as a dam, by first forming it with one of its ends resting upon a support adjacent to the body of water in which it is'intended to lie, and with the base of the structure extending upwardly and facing the body of water. Thereafter, I cause the structure .to so fall upon and through the body of water that its base comes to rest upon a predetermined area of the water bed. Although the support upon which the structure is built may be natural rock, if such' a suitablefoundation is available at the required site, is usually necessary to provide a special support. In forming the structure of concrete or other suitable cementitious material, as is preferred, proper forms are first placed upon the support, reinforcing material arranged within them as desired, and the concrete then poured and permitted to set. its support, the support is preferably so constructed that a portion of it adjacent to the body of water may be so removed that the structure will then fall in a path which can be predetermined.

Various factors must be taken into consideration to causea structure to fall in the desired position on a water bed, the contour of which usually varies materially throughout To cause the structure to fall from a given area. To prevent the structure from being destroyed, as it would be by the momentum of its fall if brought to rest on a bed with which the base of the structure does not conform, and also to form a suflicient seal between the bed andbase of the structure, it is necessary to shape the base of the structure in conformity with the contour of-the area of the water bed on which the structure is to lie, and to so position the structure upon a support that when the structure falls it will rest on that area of the water bed. Among the factors to be taken into consideration in position ing the structure to cause it to thus fall upon a desired water-bed area are the approximate depth of water through falls after its base strikes the surface of the water, the variable cushioning elfect of the water as the base of the structure variably approaches the water bed, and the momentum of the falling structure, its momentum being determined from its mass coupled with its falling velocity at variable distances from its originally supported end, A its centrifugal force, and the falling resistance imposed upon it by the support.

which the structure so I have discovered that by properly taking into consideration these and related factors, a large monolithic obelisk can be formed on it end and so caused to fall upon and through a ody of water that its base will rest quite accurately in a desired position on a water bed. .-I made this discovery in the building of a dam in a swiftly flowing stream of water, and under other conditions which will presently be explained with reference to the accompanying drawings, of which Fig. 1 is a side view of the obelisk or dam and its end support, and a vertical sectional view of the water bed on which this portion of the dam was caused to fall, the dam being shown in dotted lines in its final and in three of its intermediate falling positions; Fig. 2 a side view of a sectional structure illustrating a modification of my invention and Figs. 3 and 4 plan and side views, respectively, of a modified form of structure which may be built according to my invention.

In the building of a large storage water dam across the Saguenay River in Canada it was deemed necessary to divert the flow of water from the bed of the river which had a normal low water flow of approximately 35,000 cubic feet per second, a minimum ve locity of 20 feet per second, and a possible maximum flow of some 400,000 cubic feet per second, which conditions made the problem of constructing a cofi'erdam one of unusual magnitude. After having first provided a diversion channel ready for use upon the dam ming of the main channel, I constructed at a suitable point on the side of the channel a pier 1 upon which I formeda monolithic concrete dam 2 resting upon the pier. On the opposite bank of the river an abutment pier 3 was constructed inrelatively shallow water, the adjacent faces of the piers 1 and 3 being farther from each other than the length of the obelisk or dam 2.

Pier 1 was so constructed of reinforced concrete as to have a main bearing surface 5, a front bearing surface 6 at the top of a wall or column 7, and a downwardly-curved rollway 8 between the main and front bearing surfaces. The curvature of the rollway was determined by calculating the theoretical path through which the dam would be required to fall, after removal of the wall or column 7, to come to final rest in the desired area of the river bed. In such calculations,

the air resistance which would be encountered by the falling dam was considered to be negligible, and the coefficient of friction between the rollway surface 8 and the base of the dam in contact with it before the dam fell free from the rollway was assumed, giving due consideration to the weight of the falling mass and other factors entering into the determinationof friction. The cushioning effect of the water upon the falling of the dam was determined by assuming that moand the remaining bearing surface 5 of the pier was covered with a heavy coating of bituminous paint to minimize any bond that might be formed between it and the surface of the dam resting on it. Heavy paper or other bond-preventin material may be similarly used. To quickly and effectively remove the wall or column 7 of pier 1, a plurality of explosive-receiving tubes 10 were placed in the pier inthe desired cleavage plane thereof extending downwardly from the top of the pier at the lower end of rollway 8, these pipes being later filled with charges of dynamite from their upper open ends.

Upon this pier the dam 2 was formed of concrete suitably reinforced with cables and bars to preclude the possibility of its becoming shattered by impact upon the river bed. The dam contained about 5,500 cubic yards of concrete, weighed about 11,000 tons, was 45 feet across its breast, hada maximum depth of about 40 feet, and was 92 feet in length. For the reasons previously explained, the upwardly disposed face of the dam adjacent to the river was molded to conform substantially with the contour of the portion of the, river bed on which it was intended that the dam should lie. The dam was so positioned on pier 1 that the center of gravity of its mass was above rollway 8, and in such position as to give the dam an initial overturning moment of 75,000,000 footpounds upon the removal of the wall or column 7 forming the forward portion of the supporting pier.

The felling of the dam was effected by the removal of wall or column 7, which was blasted off by the discharge of the dynamite placed in tubes 10. In Fig. 1 there are shown by dotted lines 2a, 2b and 20 three of the several positions through which it was calculated that the damwould pass, and through or near which, by moving pictures taken of the dam during its fall, it was found it actually did pass. The position 2a of the dam shows itsbase rolling upon the lower portion of rollway 8, and the position 2?; shows it falling free from the pier with the portion of the base of the dam adjacent to the pier entering the surface of the river which is indicated by the dotted line 15.

In thus causing a massive structure to fall into and through a body of water in such a manner that it will come to rest on a predetermined area of the water bed, it is de sirable to so control its fall that its base progressively contacts with the surface of the water. Such progressive contacting with the surface of the water is shown in the position 2b of the falling dam where the end of the dam adjacent to pier 1 has entered the water. I have found that if the base of such a falling body does not thus gradually enter the water, the mass cannot be caused to fall accurately upon a predetermined area of the water bed.

In the dotted line position 20 of the-dam, the portion of its base adjacent to pier 1 is nearer to the bed of the river than the portion thereof adjacent to pier 3. In such position, the water pressure on the base is greatest where thedepth of. water is least.

This factor was taken into consideration in causing the dam to fall upon a given area of the river bed, it being predetermined, and confirmed by the fall, that the dam would move to the right, as viewed in Fig. 1, as its base approached the river bed with greater water pressure under its left than its right portion. The time of fall of the dam was approximately six seconds. That a mass such as this can be caused to fall in a desired position in a body of water is shown by the fact that the dam came to rest on the river bed within approximately one inch of its intended position. As recorded by instruments attached to the dam, its force of impactupon the bed of the river was equivalent to that which would have been causedby an uncushioned free fallof only about four inches. The dam retained its unitary character after falling from its upright position to the bed of the river, showing that the cushioning effect of the water was such as to prevent destruction of or injury to the massive structure.

Because of the magnitude of the operation involved in the example of the practice of my invention above explained, I considered it desirable to leave substantial spacesbetween the assumed final resting places-of the ends of the dam and the adjacentgfaces of piers 1 and 2. After the dam had been caused to fall, these spaces were readily and quickly sealed by the use of stop logs, and such slight sealing ofthe bottom of the dam as was necessary was done by the use of loose rocks, sand and clay. As determined by the actual practice of the invention, such end gaps may be materially reduced. By providing the ends of dam 2 and the adjacent faces of piers l and 3 with oppositely disposed slots 35 and 36, respectively, stop logs 37 may be quickly placed in the slots to close the gaps between the piers and the ends of the dam. I, v

In addition to the building of dams in the manner explained, my invention is also applicable to the building of other massive structures resting upon the beds of bodies of water. For example, my invention is applicable to the building of breakwaters, boa-t landing piers, and the like, either extending outwardly from the edges of and into bodies -tu1'e being formed of several units successively caused to fall upon predetermined areas of a water bed. In thus sect-ionallybuilding a massive structure, the first unit 20 may be formed on a shore orother pier 21, as shown in dotted lines, and caused to fall from it and onto the water bed in the manner explained with reference to Fig. 1. A second unit 22 may then be formed on the outer end of unit 20 which may be provided with a removable wall or pier 23 adjacent to a rollway. In "this manner each successive unit may be built upon and caused to fall from the outer end of the last-fallen section of the structure until the desired number of units to form the entire structure are in place.

Furthermore, as shown in Figs. 3 and 4, a da1n,or a unit of a sectional structure, may be constructed in cellular form, rather than in a solid mass. As there shown, a dam is formed of side walls 25, end walls 26, and intermediate longitudinal and transverse walls 27 and 28 with' open spaces 29 bounded by them. These open spaces extend from the top to the bottom of the structure so that as it falls into a body of water the structure will sink to the bed thereof, water coming be desirable to partially control the fall of a massive structure by anchoring its end to its foundation pier by means of cables and the like, and in some cases it may be desirable to effect the fall of a vertically erected structure otherwise than by removing a portion of its supporting pier, whether such pier be constructed in the manner shown and described, or be formed of natural rock.

According to the provisions of the patent statutes, I hEHQ explained the principle and mode of operation of my invention, and have given specific examples of how it has been and may be practiced. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced Otherwise than as specifically illustrated and described.

I claim as 'my invention:

1. The method of building a massive structure resting upon/the bed of a body of water, comprising first forming the structure with one of its ends resting upon a support ad acent to the body of Water and with its base upwardly disposed facing the body of water and shaped to substantially conform to an area of the water bed, and then causing the thus-formed structure to fall as such upon and through the body of Water until the base of the structure rests upon said area of the water bed.

2. The method of building a massive structure resting upon the bed of a body of water, comprising first forming the structure with one of its ends resting upon a support adjacent to the body of water and with its base upwardly disposed facing the body of water and shaped to substantially conform to an area of the water bed, and then removing a portion of the structure support adjacent to the body of water to cause the thus-formed structure to fall as such upon and through the body of water until the base of the structure rests upon said area of the water bed.

3. The method of building a massive monolithic structure resting upon the bed of a body of water, comprising first forming the structure of cementitious material with one end of the structure resting upon a support adjacent to the body of water and with its base upwardly disposed facing the body of water and shaped to substantially conform to an area of the water bed, and then causing the thus-formed structure to fall as such upon andthrough the body of water until the base of the structure rests upon said area of the water bed.

4. The method of building a massive structure resting upon the bed of a body of water, comprising first forming the structure, with one of tis ends resting upon a support adjacent to the body of water and with its base upwardly disposed facing the body of water and shaped to substantially conform to an area of the water bed, and then causing the thus-formed structure to fall as such with its base progressively contacting with the surface of the water and then passing through the body thereof until it rests upon said area of the water bed.

5. The method of damming a stream of water, comprising first forming a dam for the stream with one end of the dam resting upon a support adjacent to one side of the stream and with the base of the dam upwardly disposed facing the body of the stream and shaped to conform substantially to an adjacent area of the bed of the stream, and then causing the thus-formed dam to fall as such upon andthrough the stream untilthe base of (the dam rests upon said area of the stream be 6. The method of sectionallybuilding a massive structure resting upon the bed of a body of water, comprising first forming an end section of the structure with one of its ends resting upon a support adjacent to the edge of the body of water and with its base upwardly disposed and facing the body of water, then causing the thus-formed section to fall as such upon and through the body of water until its base rests upon the water bed, and similarly building each succeeding section upon and causing it to fall from the outer end of the last-fallen section of the structure.

In testimony whereof, I sign my name.

JAMES W. RICKEY. 

